Power steering pump flow (1 Viewer)

[Cdaniel]

I'm not particularly "hardcore", but I figure this crowd might have the most insight on non stock power steering issuses.

I've installed a saginaw p-series pump reworked to flow 3 gpm and 1500 psi. It has a remote resevoir with -10AN for the return.

After a lot of bleeding it seems to create it's own air. It's quiet to start, then slowly develops the air whine and the fluid is frothy. After shut down the resevoir level is high and the pump slowly burps it back down.

I'm thinking maybe the return is restricting and its somehow pulling air elsewhere? Just a SWAG. Is -10 AN not enough?

 

[Bret]

How long is the suction side, and how high above the inlet to the pump is the fluid level? Any filters inline etc? I have -10 on mine with no worries. Is the system completely bled? Took awhile with the truck off and on the get the air out. Not sure on the 3gpm, restriction on the return side shouldn't cause it, presuming -6 for the pressure side and return?

 

[Cdaniel]

How long is the suction side, and how high above the inlet to the pump is the fluid level? Any filters inline etc? I have -10 on mine with no worries. Is the system completely bled? Took awhile with the truck off and on the get the air out. Not sure on the 3gpm, restriction on the return side shouldn't cause it, presuming -6 for the pressure side and return?

Suction side is about 6 inches long and well above the pump. Pressure side is std saginaw flared hose and the return to the res is 3/8 push lock to -6.

I was just reading tech on the PSC site and they advise against a non baffled resevoir, which I have. Maybe the return is aerating the fluid?

Maybe I need to keep at the bleeding process.

 

[Bret]

You could take the cap off and watch inside while someone else starts it? I am not sure on the sag box, but I did my best to "bench bleed" everything before I connected the together. I cycled everything with the front tires off the ground and the engine off, then started it till it frothed, stopped and let the bubbles come out of suspension and repeated. It took awhile.

 

[Cdaniel]

Talked with the pump builder today and they claim they have seen air get drawn into the return from hose connections that don't leak otherwise. Try clamping all of the push lock connections.

So I did. Same result.

Tried a temporary baffle in the reservoir too. Might have helped some, but the air still returns.

Here's a pic of the set up

 

[Cdaniel]

Resolved I think. The solution was reworking the crappy low budget reservoir. The feed to the pump was actually a -10 AN fitting adapted to a pressed in fitting that was closer to -6 I knocked that out and welded the -10 to the can. I think the pressed in part may have been pulling air too. Next I drilled the return port through so the fluid wasn't slamming into a wall and redirected 90 degrees. Now I have a nice smooth return flow and no bubbles coming out. No noise. We'll see how it goes on the road. Added a cooler while I was at it too.